Thomas Bradley was a colleague of Professor Phineas Horton, and worked
with him on a certain project involving a "synthetic man--an exact replica
of a human being" who would burst into flames when exposed to air. This
project eventually became the Human
Torch (I). Dr. Bradley was irritated at not getting any
of the credit and became embittered. He began calling himself "Doctor Death,"
created a knockout gun and another android, Volton,
and used them on the side of evil. He allied with the Nazis and was a member
of the Battle-Axis, along with the Human
Meteor, Volton, Strongman,
and
Spider
Queen, when they fought against the Invaders.

At the end of the battle with the Invaders Bradley was killed by Volton.

Note: Doctor Nemesis first appeared in Super Mystery Comics
v3 #3 (Summer 1942). However, as a Marvel character, he is a retcon addition,
not having appeared in a Timely book.